Apparatus for sorting letters, packets, and other articles



April 15, 1930. v A. G. STRATHERN 1,754,726

APPARATUS FOR SORTING LETTERS, PACKETS, AND OTHER ARTICLES Filed May 2, 1929 4 Sheets-Sheet l INYENTOR A G STRA'I'HERN April 15, 1930. A. G. STRATHE RN 1,754,726v 7 AND OTHER ARTICLES APPARATUS FOR SORTING LETTERS, PACKETS,

Filed May 2, 1929 4 Sheets-Sheet INVEN TOR Al: .STRATHERN April 15, 1930. A. G. STRATHERN 4, 2

APPARATUS FOR SORTING LETTERS, PACKETS, AND OTHER ARTICLES Filed May 2, 1929 4 Sheets-Sheet 3 FIGB.

- INVENTGR A G STRATHERN ATTYS April 15, 1930. 'A. G. STRATHERN 1,754,726

APPARATUS FOR SORTING LETTERS, PACKETS, AND OTHER ARTICLES Filed May 2, 1929 4 Sheets-Sheet 4 INVENTOR.

3 ATI'YS.

A-G-STRATHERN.

i 25 tended destinations.

Patented Apr. 15,1930

UNITED STATES PATENT OFFICE ALEXANDER GEORGE STRATHERN, OF GLASGOW, SCOTLAND APPARATUS FOR SORTING LETTERS, PACKETS, AND OTHER ARTICLES Application filed May 2,1929, Serial No. 359,978, and in Great Britain May 18, 1928.

This invention relates to apparatus for sorting letters, packets, or other articles, of the type comprising endless conveyor bands adapted to circulate past sorting stations where the letters are deposited by sorters on to the bands.

Apparatus according to the invention comprises a plurality of endless conveyor bands arranged in superposed relation upon a common driving pulley and diverging from the upper side of said pulley so that the upper flights of said bands are conveniently spaced apart, being guided for example by means of anti-friction rollers or the like.

The superposed and spaced upperflights of the conveyor bands extend horizontally with in a housing or structure provided with slotted grids of which the slots register one u with each upper flight ofthe bands and of which the bars intermediate the slots bear indications of destination, the arrangement being such that sorters stationed at the several grids can conveniently place the letters or the like on thebands corresponding to the in- At suitably spaced points beyond the last sorting station the bands are guided, for example, by means of guide rollers, so as to descend towards the lower flights, in consequence of which the letters or other articles carried by each band are dropped at the position of the return bend of the said band.

Chutes or the like are disposed adjacent to the several return bends. At the bottom of each chute is a small endless conveyor belt for removing the letters or the like. As the letters or the like approach the lower end of the chute on the moving conveyor belt they are engaged by rotating cams whereby they are lifted clear of the belt and stacked at the bottom of the chute, the letters already stacked being lifted by the cams to permit the insertion of the succeeding letters into the bottom of the stack. Each chute is also provided with adelivery nozzle adaptedtocause deflection of each letter or the like as it is led from thechute by the small conveyor, whereby theletters or the like are turned round as they issue from the chute.

In the accompanying drawings Figs. 1 and 2 are more or less diagrammatic side elevations showing, respectively, the front or driving end and the rear or deliveryend of a double-sided sorting apparatus constructed in accordance with the invention; Fig. 3 is a cross-section on the line 33 of Fig. 2; Fig. 1

is a fragmentary detail section; Figs. 5 and 6 are detail views at right angles to each other showing a delivery chute; Figs. 7 and 8 are detail views at right angles to each other, showing the arrangement of the band guiding rollers and the band tensioning mechanism at the delivery end of the apparatus. Fig. 9 is a view corresponding to Fig. 3 showing a modification.

Referring to Figs. 1 to 8, at each side of the apparatus is a driving pulley 1 wrapped by a plurality of endless conveyor bands 2 arranged in superposed relation. The u er flights of the bands diverging from the pulley are guided by horizontally disposed antifriction rollers or the like (not shown) and .thenceextend horizontally towards the de livery end of the apparatus over vertically spaced horizontal trays or shelves 3 (Fig. 3) extending longitudinally of the apparatus and sustained by spaced frame members 4. In the embodiment illustrated there are thirty conveyor bands 2 and thirty trays 3, one for each conveyor band.

At the delivery end, the bands 2 are directed downwardly over spaced anti-friction rollers 5. The lower or return flights 2 are led horizontally in superposed relation back to the underside of the driving pulley 1 being supported on shelves 6 sustained by the franiest (Fig.

Disposed at spaced points opposite the upper flights of the bands are grids 7 each presenting two relatively staggered rows of slots 8 (Fig. 1). Each slot 8 registers with a band so that letters inserted through the slots may be deposited on the corresponding bands. The bars 9 (Fig. 4) intermediate the slots 8 present inclined front faces 10 on which are imprinted the destinations of letters to be inserted through the slots.

The rollers 5 at the delivery end of the ap paratus are sustained by stationary bars 11 (Figs; 7 and 8). The bands have substantially vertical portions 2" extending between the lowermost rollers 5 and rollers 12 sustained by a stationary bar 13 disposed below the bars 11. Each band, after wrapping its roller 12, passes over a jockey roller 14 and under another roller 15 also sustained by the bar 13. The rollers 14 are carried by nutforming members 16 penetrated by vertical screws 17 and by guide rods 18. The lower ends of the screws 17 carry gear pinions 19 meshing with ear pinions 20 secured to spindles 21 journa led in brackets tired to a bar 23 beneath the bar 13. V The arrangement is such that, when the spindles 21 are rotated by means of a key or the like, the nut-forming members 16 and therewith the jockey rollers 14 are raised or lowered relatively to the rollers 12, 15 whereby the relative bands are tensioned or slackened as required. It will be understood that although band guiding rollers and band tensioning mechanism for only three bands are shown in Figs. 7 and 8 there are provided a lurality of similar devices for tensioning al the bands.

Alternating with the vertical delivery end portions 2 of the bands are inclined chutes 24 (see particularly Figs. 5 and 6) at the bottom of each of which is arranged an inclined endless conveyor belt 25 wrapping an upper roller 26 and a lower driven roller 27. Rotatable with the roller 27 are discs, one on each side of the conveyor belt 25, presenting on their peri heries fingers 28 which pro'ect above the elt 25.

'I ensioning of the conveyor belt 25 may be effected by rotation of a screw 29 (Fig. 6).

In operation, sorters standing opposite the several ids 7 insert letters into the appropriate s ots 8 so that they are deposited on to the corresponding travelling bands 2. when the letters reach the delivery ends of the bands they drop by gravity on to the relative conveyor belts 25, the chutes 24 of which bear corresponding destination marks. As one lower corner 0 a letter engages the conve or belt 25, the letter being contained in a substantially vertical plane, as it moves with the conveyor belt, is engaged by projections 30 Figs. 5 and 6) on the delivery nozzle 30 of t e chute whereby the letter is overturned and deposited flatwise on the conveyor belt. The letters, as the are delivered on the belt 25, collect in stac ed formation at A above the rotating fingers 28 at the bottom of the chute 2.4, in that as each successive letter approaches the bottom of the chute, the fingers 28 lift the already stacked pack to permit the insertion into the stack of the arriving lettor, the letters being thus stacked from the bottom.

The driving pulleys 1 at each side of the apparatus are secured to a common shaft 31 carrying intermediate said pulleys a worm wheel 32 meshing with a worm 33 driven by an electric motor 34. Chain driven from the shaft 31 is a shaft 35 carrying pulleys 36 serving to drive conveyor belts 37 moving in troughs 38 disposed one along each side of the apparatus and adapted to convey the letters to the sorters working at the several grids 7. The belts 37 wrap pulleys 39 located at the delivery end of the apparatus.

Letters or packages too bulk to be inserted into the slots 8 are placed y the sorters on an overhead conveyor belt 46 working in a trough 41 and are returned to the front end of the apparatus through a chute 42. The conveyor belt wraps pulleys 43, 44 disposed, respectively, at the front end and at the delivery end of the apparatus,the pulley 43 being mounted on a shaft 45 interconnected by gearin 46 to a shaft 47 chain-driven from the sha, 35..

48 denotes glass panels arranged along the sides of the apparatus intermediate the grids 7 and the frames 4.

In the simpler embodiment of the invention shown in Fig. 9 there are provided a single driving pulley 1 and a single set of superposed bands 2, there being a series of sorting stations at each side of the apparatus and the chutes 24 being arranged at one side only.

What I claim is 1. Apparatus for sorting letters, packets or other articles comprising a housing provided with a series of slotted grids, a driving pulley at one end of said housing, a plurality of endless bands arranged in superposed relation upon said pulley and diverging from the upper side of said pulley so that the upper flights of said bands are spaced apart, said upper flights extending substantially horizontally along said housing opposite the slots in said grids, and chutes located at the return bends of said bands for collection of letters or the like delivered by said bands.

2. Apparatus for sorting letters, packets or other articles comprising a housing presenting a series of spaced sorting stations, :1 driving pulley at one end of said housing, a plurality of endless bands arranged in superposed relation upon said pulley and diverging from the upper side of said pulley so that the upper flights of said bands are spaced apart, said upper flights extending substantially horizontally within said housing opposite said sorting stations, chutes located at the return bends of said bands for collection of letters or the like delivered by said bands, endless conveyors associated with said chutes, and stacking devices to which letters or the like are conveyed by said conveyors.

3. Apparatus for sorting letters, packets or other articles comprising a housing presenting a series of spaced sorting stations, a driving pulley at one end of said housing, a plurality of endless bands arranged in superposed relation upon said pulley and diverging from the upper side of said pulley so that the upper flights of said bands are spaced apart, said upper flights extending substantially horizontally within said housing opposite said sorting stations, chutes located at the return bends of said bands for collection of letters or the like delivered by said bands, endless conveyors associated with said chutes, and deflecting devices for deflecting letters or the like descending said chutes.

In testimony whereof I have signed my name to this specification.

ALEX. G. STRATHERN. 

